There is air that cools your refrigerator that blows over from the freezer
powered by the freezer fan, thats where all of the cold in the fresh food section originates. And regardless whether or not the fresh food circulation fan stops working the damper that stops the air flow from the freezer must close or the air is going to continue to flow in. That damper is also powered by the main board which takes temperature readings from a thermistor in the fresh food section. The main board also closes that damper when the door is open for a couple of minutes.
According to the description of your problem the damper will be most likely stuck or broken, that is very common with this model.
The red arrows indicate the parts that need to be removed and the blue arrow shows the foam housing the damper is in.
Once the fridge gets cold enough the damper is supposed to shut. This does not mean the unit shuts off, it will continue to run until the freezer gets to the temperature it is supposed to be. If the damper stays open then that air continues to circulate over to the fridge.
UNPLUG THE UNIT
You will need to remove everything from the fridge including the shelves and drawers. Remove the light cover and fixture. Go to the rear wall and remove the cooling tower on the rear wall. Then you can access the damper. Once get it off see that it opens and closes with your fingers. Or if it is broken.
The damper comes as an entire assembly and cannot be purchased any other way. The part number is XXXXX That is a factory part number you can shop anywhere with. One place that has it online with a picture you can look at is LOCATED HERE.
If you do not find that damper broken please let me know.
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